East Hampton town and village will team up to test the groundwater around utility poles on Cedar Street in East Hampton for the presence of pentachlorophenol, or penta, a wood preservative that some residents believe is toxic and polluting local water.

Long Island Businesses for Responsible Energy, an East Hampton-based nonprofit, has been urging the town and village to conduct tests after the group hired Dermody Consulting, an environmental consulting firm, in April to test soil around utility poles recently installed by PSEG. Dermody concluded that the soil surrounding the poles contained nearly 300 times the State Department of Environmental Conservation’s limit for penta, leading the nonprofit organization to believe the water table also could be at risk.

While town and village officials say they recognize possible dangers from the chemical, Town Supervisor Larry Cantwell said the testing is being done to ensure the highest level of precaution but is not meant to instill fear in residents.

“I don’t want to get ahead of what the tests will or will not show,” he said on Friday. “The issue of penta has been raised as a toxin, and there’s certainly some truth to that, given it’s been banned in every other application in the U.S. except as a wood preservative. But I think we need to see if penta is present in the groundwater, and if that’s related to the penta in the utility poles.”

Mr. Cantwell said the town, with the help of Village Administrator Becky Molinaro, has identified an area near the Emergency Services Building on Cedar Street, in the vicinity of the new poles, that will be tested. Ms. Molinaro said the village will bring in a third-party expert opinion.

“The area is down-gradient,” said Ms. Molinaro, explaining that down-gradient area forces water to stream and eventually pool into a larger body of water. “So the tests will, hopefully, be able to tell if the water traveling past these poles is being contaminated.”

Ms. Molinaro said the town and village are taking steps to give residents some peace of mind, especially after the Suffolk County Water Authority refused the village’s request to test the water. “They have very strict testing standards,” she said of the water authority’s decision. “They’d never detected penta in any of the water, and they’re confident in what they have found. But the town and village wanted to take the next step and address the concerns.”

State officials are also hoping to provide residents with relief from penta. Assemblyman Fred Thiele and Senator Ken LaValle in September introduced legislation that would ban the use of the chemical in utility poles across the state.

“In essence, we’re proposing to prohibit the use of PCP [penta] to treat utility poles for anywhere that gets its drinking water from aquifers, which is all of Long Island,” Mr. Thiele had said previously. “And for those that are already in the ground, it would require the utility company to post a notice on every other pole about the dangers of PCP.”

Mr. Thiele continued to say that the use of penta on utility poles is meant for places where poles are not 20 feet from residents’ homes. But in the case of East Hampton, he said the “letter of the law” has not been met.

“To me, that isn’t consistent with the spirit or the letter of what the [Environmental Protection Agency] is talking about,” he said of allowing penta to be used in utility poles as a wood preservative only.

Water testing is set to begin within the next week, Ms. Molinaro said, and the results are expected a few weeks after testing is complete.

“We certainly hope we have safe drinking water,” said Ms. Molinaro, “and at the end of the day, we want to ensure that that’s what’s happening. But should something come back that is causing alarm, we’d take it to the appropriate agencies and hope they would address and remedy the problem as soon as possible.”